In utero cocaine, discriminative avoidance learning with low-salient stimuli and learning-related neuronal activity in rabbits (Oryctolagus cuniculus).

Daily injections of cocaine administered to pregnant rabbits (Oryctolagus cuniculus) throughout gestation were associated with neural and behavioral changes during development and in adulthood, including altered neuron structure and function in areas receiving dopaminergic projections and retarded Pavlovian eyeblink conditioning with low-salient conditional stimuli. Studies of discriminative avoidance learning have shown changes in learning-related cingulothalamic neuronal activity, but no behavioral learning impairment in cocaine-exposed offspring. Here, low-salient stimuli were used during discriminative avoidance conditioning. Impairments early in behavioral acquisition were found, as well as alterations of anterior cingulate and medial prefrontal cortical, medial dorsal thalamic, and amygdalar neuronal response profiles and learning-related neuronal activity. These results elucidate the neural processes, impaired by prenatal cocaine, that support conditioning with low-salient stimuli. (c) 2003 APA, all rights reserved